code: def test_multiplexed_multiple_replicas(serve_instance):
      """Test multiplexed traffic can be sent to multiple replicas"""
      signal = SignalActor.remote()
  
      @serve.deployment(num_replicas=2, max_concurrent_queries=1)
      class Model:
          @serve.multiplexed(max_num_models_per_replica=2)
          async def get_model(self, tag):
              return tag
  
          async def __call__(self):
              tag = serve.get_multiplexed_model_id()
              await self.get_model(tag)
              await signal.wait.remote()
              # return pid to check if the same model is used
              return os.getpid()
  
      handle = serve.run(Model.bind()).options(multiplexed_model_id="1")
      pid1_ref = handle.remote()._to_object_ref_sync()
      # Second request should be sent to the second replica
      pid2_ref = handle.remote()._to_object_ref_sync()
      signal.send.remote()
      assert ray.get(pid1_ref) != ray.get(pid2_ref)
  
      wait_for_condition(
          check_model_id_in_replicas, handle=handle, model_id="1"
      )
  
imports: import asyncio
  import os
  from typing import List
  import pytest
  import requests
  import ray
  from ray import serve
  from ray._private.test_utils import SignalActor, wait_for_condition
  from ray._private.utils import get_or_create_event_loop
  from ray.serve._private.constants import SERVE_MULTIPLEXED_MODEL_ID
  from ray.serve.context import _get_internal_replica_context
  from ray.serve.handle import RayServeHandle
  from ray.serve.multiplex import _ModelMultiplexWrapper
label_desc: Use image node_id 7 for calling a global function with example usage: test_multiplexed_multiple_replicas(serve_instance) and returns: tag, os